Progress of Theoretical Physics

On the Ordering Independence of the Path Integral Formalism

Tarō Kashiwa

Published Dec 1, 1980• 5 citations

Abstract

It is shown that a path integral expression of the generating functional is independent of the ordering scheme one employs. The essential point is that {(Gl,l-Gl,l-1)-(Gl-1,l-Gl-1,l-1)}/ Δt is not of order Δt but of order unity, where Gj,k is the propagator. We also discuss the case of fermion and obtain the same conclusion. Thus one may choose any ordering scheme suitable for the problem under consideration even in the path integral formalism.

DOI: 10.1143/ptp.64.2164

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